In July 2000, Disney was destroying the old Horizons
building to clear the space for Mission Space.†
Here are two videos of the Epcot Monorail running through Epcot showing
the destruction of the building†† clip1 (2.3 megs) clip2
(1.1 megs)

This video is of the
express monorail from the ttc to MK as seen from the front cab of the
monorail. Watch as you go through the Contemporary Hotel and see Space Mountain
before arriving at the Magic Kingdom monorail station.† 4:40 length 3.5 megs